If the heights of American adult males are normally distributed with a mean of 177 cm and a standard deviation of 7.4 cm. Tthe range of heights that contain:
(a) 68% of the data falls within the range of 169.6 cm - 184.4 cm.
(b) 95% of the data falls within the range of 162.2 cm - 191.8 cm.
(c) 99.7% of the data falls within the range of 154.8 cm - 199.2 cm.
What is Range of heights?
(a) Range of heights:
Lower range: Mean - 1 standard deviation
Lower range = 177 - 7.4 = 169.6 cm
Upper range: Mean + 1 standard deviation
Upper range = 177 + 7.4 = 184.4 cm
(b) Range of heights:
Lower range: Mean - 2 standard deviations
Lower range = 177 - (2 * 7.4) = 162.2 cm
Upper range: Mean + 2 standard deviations
Upper range = 177 + (2 * 7.4) = 191.8 cm
(c) Range of heights:
Lower range: Mean - 3 standard deviations
Lower range = 177 - (3 * 7.4) = 154.8 cm
Upper range: Mean + 3 standard deviations
Upper range = 177 + (3 * 7.4) = 199.2 cm
Therefore:
(a) 68% of the data falls within the range of 169.6 cm - 184.4 cm.
(b) 95% of the data falls within the range of 162.2 cm - 191.8 cm.
(c) 99.7% of the data falls within the range of 154.8 cm - 199.2 cm.